The present invention generally relates to a collision avoidance system, and more particularly to a system that retransmits a brake warning throughout a line of braking vehicles.
Current interest in collision avoidance systems for automotive applications is rapidly increasing. This interest is due in part to the many safety benefits that a collision avoidance system provides. Many types of collision avoidance systems have been conceptualized. Several types include blind spot obstacle detection, collision detection, and backup alert warnings. These types of commonly known systems tend to be self contained xe2x80x9cimmediate areaxe2x80x9d warning systems. That is, such systems tend to provide a warning to an individual operator only in the event an obstruction is detected in the immediate perimeter of the equipped vehicle.
However, rear-end collisions tend to be the dominate type of accidents and xe2x80x9cimmediate areaxe2x80x9d warning systems fail to deter such collisions. In many cases, xe2x80x9cpilupsxe2x80x9d of three or more vehicles may occur. Further, as most rear-end collisions occur on high speed multi-lane roadways there is a greater likelihood of extensive damage to a multiple of vehicles.
FIG. 1A shows one collision scenario. The lead vehicle 9 initiates a sudden deceleration from a high rate of speed. Due to the tendency for drivers to travel closely together, the result is a multi vehicle accident as depicted in FIG. 1B. As illustrated in FIG. 1B, some vehicles 11 make contact with other vehicles while staying in the current lane, and other vehicles 13 swerve into adjacent lanes in an effort to avoid contact thereby spreading the accident to traffic in adjacent lanes.
These sudden decelerations are often the cumulative result of xe2x80x9cbrake tappingxe2x80x9d by each driver in a long line of vehicles traveling closely spaced together. Each brake tap results in the slowing of a vehicle. The following vehicle, closely spaced, observes the slowdown, takes time to react, and then also decelerates. The combined result of reaction time and slightly increased brake application along the line of vehicles causes the distance between vehicles to rapidly close. This results in a sudden stoppage or dramatic slowdown throughout the entire line of vehicles.
Known collision avoidance systems may send a signal from a slowing vehicle to the second vehicle. However, the second vehicle does not then send the signal on.
The present invention provides a collision warning system which simultaneously warns a multitude of vehicles traveling behind a vehicle initiating a sudden deceleration. The system includes a sensor for measuring vehicle deceleration, a receiver to receive a transmitted signal, and a transmitter which directionally transmits a signal in response to either the acceleration sensor or receiver. Preferably, a brake warning device is automatically actuated upon reception of the signal, and the signal is then retransmitted.
The transmitter is preferably located to transmit the signal to the rear of a vehicle and the receiver is preferably located in the front of the vehicle to receive the warning signal transmitted by a leading vehicle. Additionally, a repeater assembly automatically retransmits the warning signal received via the receiver out the rear of the vehicle through the transmitter.
The system preferably has at least two modes of warning operation, initiate warn and repeat warn. In the first mode, a vehicle initiating a sudden deceleration detects its own slowdown and transmits a warning to the rear of the vehicle. The second mode of operation does not detect deceleration but receives a transmitted warning from the vehicle(s) ahead and automatically actuates the vehicle brake lights. The warning is also simultaneously retransmitting to the rear to actuate the brake lights of the next vehicle. The present invention therefor provides an immediate warning to trailing vehicles following a lead vehicle which suddenly decelerates. A warning provided in this manner allows operators several vehicles in back of the lead vehicle to be simultaneously notified that the lead vehicle is decelerating independently of whether the intervening vehicles have manually applied their brakes. By this invention a multi-vehicle accident as illustrated in FIG. 1B is less likely to occur.